Parts & Components
The DIY Gradiometer Kit contains the main electronics and sensor components required to build a fluxgate magnetometer gradiometer.
Some mechanical parts must be provided by the user depending on the desired instrument length and mounting configuration.
This page lists:
- components included in the kit
- additional materials required for assembly
- tools needed to build the system
Kit Components
The FG Sensors DIY Gradiometer Kit typically includes the following electronics and sensor components.
FG-3+ Fluxgate Sensors
Two FG-3+ 1-axis fluxgate magnetometer sensors are used to measure the magnetic field.
The sensors provide a frequency output proportional to magnetic field strength, allowing the system to detect very small magnetic variations.
The two sensors are placed along the tube to measure the magnetic field gradient.
MAG-BOARD Electronics
The MAG-BOARD is the central processing board of the gradiometer system.
It performs several functions:
- reads sensor signals
- processes magnetic field measurements
- drives the LCD display
- controls user inputs
- provides smartphone connectivity
The board is delivered with preloaded firmware for gradiometer operation.
Sensor Cables
The kit includes cables used to connect the sensors to the MAG-BOARD.
Two cable lengths are typically provided:
- short cable for the upper sensor
- long cable for the lower sensor
Proper cable routing is important for correct assembly.
Electronics Housing
A protective housing is used to mount the electronics and display.
The housing typically contains:
- MAG-BOARD
- LCD display
- user interface buttons
- buzzer
The housing is attached to the gradiometer tube during final assembly.
LCD Display
An optional LCD display module provides real-time feedback during operation.
The display shows values such as:
- upper sensor measurement
- lower sensor measurement
- gradient value
- calibration parameters
The display contrast can be adjusted using a potentiometer on the board.
Buttons and Indicators
The gradiometer interface may include:
- NULL button for calibration
- "+" and "−" buttons for sensitivity adjustment
- LED indicators
- buzzer for audio feedback
These components allow the user to operate and tune the instrument.
Mechanical Components
Some structural parts are not included in the electronics kit and must be supplied by the user.
Tube
A plastic tube is used as the main structure of the gradiometer.
Recommended dimensions:
| Parameter | Value |
|---|---|
| Diameter | 35–36 mm |
| Length | ~1 meter (or longer depending on application) |
The tube holds the two sensors at a fixed distance to measure the magnetic gradient.
Tube Cap
A plastic tube cap is used to secure the sensor assembly at the end of the tube.
The cap also allows access to the sensor mounting screws during calibration.
Sensor Holders
Sensor holders keep the FG-3+ sensors centered inside the tube.
These parts may be:
- included in the kit
- produced using a 3D printer
STL files for printing are available on the FG Sensors website.
Mounting Brackets
Mounting brackets are used to attach the electronics housing to the tube.
These brackets help maintain mechanical stability during operation.
Required Tools
Basic Tools
- soldering iron
- screwdriver
- hot glue gun
- wire cutters
Drilling Tools
The mechanical assembly requires drilling several holes.
Recommended drill sizes: 3 mm, 6.5 mm, 10 mm.
A drilling machine or handheld drill can be used.
Optional Components
Some users may add optional components to extend the system:
- external flash memory chip
- smartphone mount
- tripod mount
- external battery pack
These additions depend on the intended application of the gradiometer.
Next Steps
After verifying that all parts are available, continue with: